This invention relates to the art of foot braces and, in particular, to foot braces especially suited for patients suffering certain physical paralysis of portions of the body due to cerebral vascular impairment, such as suffered by stroke victims.
When a patient suffers cerebral vascular impairment due to an accident or a stroke, or other causes, a common result is some degree of physical paralysis. A theory of what happens is that the impairment of the brain results in interruption or elimination of certain signals to the brain which are ordinarily transmitted from the affected body parts through neurological connections to the brain. The parts of the body affected are determined by which parts of the brain become impaired. For example, it is well known that the right side of the brain generally controls the left side of the body, and conversely. As a result, sense of touch may be diminished or eliminated and certain muscles may become substantially inactive and the patient may lose ability to adequately control movements of parts of the body on one side of the body, or both. In one extreme, a patient might completely lose the sense of where a limb is in space.
In other examples, physical impairment may manifest itself as inability to straighten the knee from a partially flexed or hyperextended position, inability to properly flex the ankle through its normal angular movement, or inability to stand in a normal erect position or move an arm or leg through its normal angular movement, or combinations of these. A typical stroke victim condition may involve some degree of paralysis of an entire side of the body with a foot dragging in a downward hanging position, an arm bent with the hand curled in a modified fist position, and a curved spine causing the patient to tilt from an erect position.
The traditional remedy for some of these deficiencies is to employ rigid bracing to force retain the body parts in a fixed and sometimes abnormal alignment of the body parts to allow the patient somewhat improved but limited use of the limbs or body parts. It would be common for a rigid brace to be applied to a dragging foot to force retain it in a position approximately perpendicular to the leg and thereby allow the patient to better use the leg for walking. Such a brace would not, however, allow any movement or flexure of the ankle as is necessary for a normal walking gait.
Another disadvantage of a rigid brace, aside from the limitations it imposes on normal limb movement, is that the forced immobility of the limb prevents use of the limb muscles and muscle atrophy and further limb disfunction may result. In cases where the muscles involved have no proprioception or neurological connections to the brain due to the nature of the cerebral vascular impairment, a rigid brace may be the best remedy available. However, if the muscles still display some proprioception with some neurological connections to the brain in sufficient amount that the muscles respond positively to physical therapy in such a way that the paralysis of the limbs involved diminishes and muscle tone improves then the patient may achieve substantial benefit from the device embodying the inventions described herein.
With the foot brace of this invention, the foot brace is fitted to the foot to substantially correct the foot position to approximate normal alignment of the ankle and foot bones. The foot brace is rigid laterally, but flexible front to back to allow front to back angular movement between the foot and ankle bone as the foot and leg travel through their ordinary paths of movement and thereby enable the patient to improve tone of the muscles associated with angular movement between the foot and ankle and avoid muscle atrophy.